Impact-absorbing elements are conventionally used in motor vehicle doors, which elements are placed between the inside door panel and a location adjacent to the passage for the window so that, in the case of a lateral impact, the occupant next to the door is subjected to only a weak impact. Furthermore, such energy-absorbing devices are so arranged that, in the case of a sufficiently great impact, the impact is transmitted to the occupant's pelvis rather than to another part of his body.
Absorbing devices have already been produced in which hollow impact-absorbing elements of generally conical shape project from a plate portion, as described in document FR-2 784 151.
However, given the considerable space that must be occupied by the energy-absorbing device, it became clear that the configuration of each hollow impact-absorbing element was not optimal, and that it was desirable to reduce the height thereof.
There were therefore produced, as described in document FR-2 815 100, energy-absorbing devices in which hollow impact-absorbing elements of reduced height are formed on two plate portions which are brought into contact so that two impact-absorbing elements are aligned in the trans-verse direction. The relative positions of the impact-absorbing elements and their particular characteristics can be adapted so that each impact-absorbing element has a configuration well suited to the impacts that are to be absorbed.
Such energy-absorbing devices having stacked hollow impact-absorbing elements are at present used in motor vehicle doors; during assembly, they are generally associated with spacers for adaptation to the width which must be occupied by the absorbing device between the inside door panel and the passage for the window associated with the door.
Accordingly, the manufacture of the elements that are ultimately fitted into the motor vehicle doors requires on the one hand the manufacture of an energy-absorbing device having hollow impact-absorbing elements, and on the other hand the manufacture of spacers, the spacers being fitted to the absorbing elements during manufacture of the motor vehicles.